Welp, as others have noted, this is a pretty terrible game. It's a very weak side-scroller with utterly terrible combat. You only have one basic attack, an ability to block, and a special attack with a long-ass wind-up. You can't even jump and the stages are just utter straight lines like those flash games from early 2000 or something.
On top of that, the translation is terrible and head-ache inducing... but even if it wasn't, there's barely any story to talk about. The main antagonist and the main boss are never shown either. They actually recycle a monster and its animation near the end even though their number of monsters was already low to begin with...
About the only good thing I can say about this is that even if you suck at these types of games (which I do btw), it shouldn't take you longer than ~45 minutes to finish it the legit way and unlock the gallery.
I'd have been impressed if they at least committed to the theme in their animations and not just the writing... That is to say The whole thing is about a Witch that summoned a girl for the sake of torturing her for entertainment. So Riona gets thrown at monsters where regardless of what happens to her, she entertains the witch. The writing implies brutality and death and whatnot, and a number of the bad ending scenes imply that Riona dies in them, but this is not really depicted aside from one in-combat animation that has a monster pierce her hands and calves with its blade limbs while it fucks her.
It's all sorts of meh... but then again, I suppose I should expect that from this particular circle, they've never done anything that's not mediocre in some way, shape or form.
All in all, not worth a single dime tbh. Might be worth wasting some time with if you like the art and want to see a couple (literally just 2) of animations with some nice stomach bulging in them, but that's it.